Characterizations of Amazonian Woods in Relation to the Evolution of Woody Plants

亚马逊是地球上生物资源的宝库之一，因为最有价值的植物物种自然生长在亚马逊河流域。然而，根据可靠的数据，由于刀耕火种的农业和过度放牧，亚马逊森林面积每年继续减少1.7万平方公里。选择和培育具有较强环境适应能力的有用树种，无论是对失去的热带雨林的恢复，还是对木材的利用，都是非常重要的课题。创造木材的新价值将导致适当砍伐和植树造林的可持续木材管理。虽然亚马逊木材的植物分类学已经得到了很好的研究，但对木材利用至关重要的木质部形态发生和木材质量评价的全面研究还很少，本研究的目的是从环境适应性和遗传分类学的角度研究影响木材质量的关键因素--细胞壁的物理化学性质。我们主要研究位于巴西西北部马托格罗索州的木本植物的木质部形态发生。亚马逊树林的比密度在0.5~1.18之间，相对高于日本树种。Angelim-Vermelho和Castanha-do-Paral的甲醇萃取物的百分含量明显较高。木质素中丁香基/愈创木基比为0.6~1.77。

Amazonia is one of the treasures for bioresources on the earth, since the most valuable species of plants grew naturally in the Amazon river basin. However, according to a reliable data, 17,000km 2 of the Amazonian forest area continues to be lost every year by slash-and-burn agriculture and over-pasturage. Selection and breedings of useful woods which have high abilities of environmental adaptation are very important subjects for not only restoration of the lost tropical rain forest but also for utilization of woods. Creation of new value of woods would lead to a sustainable wood management of appropriate deforest and afforestation. Although plant taxonomy on Amazonian woods has been well studied, there are few comprehensive researches about xylem morphogenesis and evaluation of wood quality that are essential for wood utilization.Our purpose of this work is to investigate physicochemical properties of the cell wall, which is a critical factor affecting the wood quality, in terms of environmental adaptation and genetic taxonomy. We focus on xylem morphogenesis of woody plants ranging over Mato Grosso located in the northwest region of Brazil. The specific densities of Amazonian woods were 0.5〜1.18, which are relatively higher than that of Japanese species. The MeOH-extractives of Angelim-Vermelho and Castanha-do-Paral showed significantly high percentages. Syringyl/Guaiacyl ratios in lignin ranged from 0.6 to 1.77.